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1.
Breast Cancer Res Treat ; 204(3): 521-530, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38194131

RESUMO

PURPOSE: Boswellic acids, active components of frankincense, suppress tumor proliferation in vitro with a strong clinical trial safety profile in patients with inflammatory diseases. We performed a Phase Ia window of opportunity trial of Boswellia serrata (B. serrata) in patients with breast cancer to evaluate its biologic activity and safety. METHODS: Patients with invasive breast cancer were treated pre-operatively with B. Serrata (2400 mg/day PO) until the night before surgery for a median of 11 days (SD 6 days; range: 5-23 days). Paraffin-embedded sections from pretreatment diagnostic core biopsies and post-treatment surgical excisions were evaluated using a tunnel assay and immunohistochemistry staining with Ki-67 antibodies. A non-intervention retrospective control arm consisting of core and surgical tissue specimens from untreated patients was used to compare patients treated with B. Serrata. The change in proliferation and apoptosis between diagnostic core specimens and surgical specimens was compared between the control and treatment groups using a two-tailed paired t-test. RESULTS: Twenty-two patients were enrolled, of which 20 received treatment, and 18 had sufficient tissue for IHC. There was an increase in percent change in proliferation from core biopsy to surgical excision in the control group (n = 18) of 54.6 ± 21.4%. In the B. serrata-treated group there was a reduction in proliferation between core biopsy and excision (n = 18) of 13.8 ± 11.7%. This difference was statistically significant between the control and B. serrata-treated groups (p = 0.008). There was no difference in change in apoptosis. There were no serious adverse events related to the drug. CONCLUSION: Boswellia serrata inhibited breast cancer proliferation and was well-tolerated in a Phase Ia window of opportunity trial.


Assuntos
Boswellia , Neoplasias da Mama , Franquincenso , Triterpenos , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Estudos Retrospectivos , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico
2.
J Nat Prod ; 87(3): 560-566, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38383319

RESUMO

Manzamine-A is a marine-derived alkaloid that has demonstrated antimalarial and antiproliferative properties and is an emerging drug lead compound as a possible intervention in certain cancers. This compound has been found to modulate SIX1 gene expression, a target that is critical for the proliferation and survival of cells via various developmental pathways. As yet, little research has focused on manzamine-A and how its use may affect tissue systems including bone. Here we hypothesized that manzamine-A, through its interaction with SIX1, would alter precursor cells that give rise to the bone cell responsible for remodeling: the osteoclast. We further hypothesized reduced effects in differentiated osteoclasts, as these cells are generally not mitotic. We interrogated the effects of manzamine-A on preosteoclasts and osteoclasts. qrtPCR, MTS cell viability, Caspase 3/7, and TRAP staining were used as a functional assay. Preosteoclasts show responsiveness to manzamine-A treatment exhibited by decreases in cell viability and an increase in apoptosis. Osteoclasts also proved to be affected by manzamine-A but only at higher concentrations where apoptosis was increased and activation was reduced. In summary, our presented results suggest manzamine-A may have significant effects on bone development and health through multiple cell targets, previously shown in the osteoblast cell lineage, the cell responsible for mineralized tissue formation, and here in the osteoclast, the cell responsible for the removal of mineralized tissue and renewal via precipitation of bone remodeling.


Assuntos
Osso e Ossos , Osteoclastos , Osteoblastos , Diferenciação Celular , Apoptose
3.
J Nat Prod ; 87(2): 217-227, 2024 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-38242544

RESUMO

The urgent need for new classes of orally available, safe, and effective antivirals─covering a breadth of emerging viruses─is evidenced by the loss of life and economic challenges created by the HIV-1 and SARS-CoV-2 pandemics. As frontline interventions, small-molecule antivirals can be deployed prophylactically or postinfection to control the initial spread of outbreaks by reducing transmissibility and symptom severity. Natural products have an impressive track record of success as prototypic antivirals and continue to provide new drugs through synthesis, medicinal chemistry, and optimization decades after discovery. Here, we demonstrate an approach using computational analysis typically used for rational drug design to identify and develop natural product-inspired antivirals. This was done with the goal of identifying natural product prototypes to aid the effort of progressing toward safe, effective, and affordable broad-spectrum inhibitors of Betacoronavirus replication by targeting the highly conserved RNA 2'-O-methyltransferase (2'-O-MTase). Machaeriols RS-1 (7) and RS-2 (8) were identified using a previously outlined informatics approach to first screen for natural product prototypes, followed by in silico-guided synthesis. Both molecules are based on a rare natural product group. The machaeriols (3-6), isolated from the genus Machaerium, endemic to Amazonia, inhibited the SARS-CoV-2 2'-O-MTase more potently than the positive control, Sinefungin (2), and in silico modeling suggests distinct molecular interactions. This report highlights the potential of computationally driven screening to leverage natural product libraries and improve the efficiency of isolation or synthetic analog development.


Assuntos
Produtos Biológicos , COVID-19 , Humanos , SARS-CoV-2 , Produtos Biológicos/farmacologia , Informática , Antivirais/farmacologia
4.
Bioorg Chem ; 143: 107103, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38211549

RESUMO

Three undescribed (1-3) and nine known (4-12) platanosides were isolated and characterized from a bioactive extract of the May leaves of Platanus × acerifolia that initially showed inhibition against Staphylococcus aureus. Targeted compound mining was guided by an LC-MS/MS-based molecular ion networking (MoIN) strategy combined with conventional isolation procedures from a unique geographic location. The novel structures were mainly determined by 2D NMR and computational (NMR/ECD calculations) methods. Compound 1 is a rare acylated kaempferol rhamnoside possessing a truxinate unit. 6 (Z,E-platanoside) and 7 (E,E-platanoside) were confirmed to have remarkable inhibitory effects against both methicillin-resistant S. aureus (MIC: ≤ 16 µg/mL) and glycopeptide-resistant Enterococcus faecium (MIC: ≤ 1 µg/mL). These platanosides were subjected to docking analyses against FabI (enoyl-ACP reductase) and PBP1/2 (penicillin binding protein), both of which are pivotal enzymes governing bacterial growth but not found in the human host. The results showed that 6 and 7 displayed superior binding affinities towards FabI and PBP2. Moreover, surface plasmon resonance studies on the interaction of 1/7 and FabI revealed that 7 has a higher affinity (KD = 1.72 µM), which further supports the above in vitro data and is thus expected to be a novel anti-antibacterial drug lead.


Assuntos
Glicosídeos , Staphylococcus aureus Resistente à Meticilina , Fenóis , Sepse , Infecções Estafilocócicas , Humanos , Antibacterianos/química , Cromatografia Líquida , Enoil-(Proteína de Transporte de Acila) Redutase (NADH) , Testes de Sensibilidade Microbiana , Espectrometria de Massas em Tandem , Relação Estrutura-Atividade
5.
Glob Chang Biol ; 28(18): 5346-5367, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35583661

RESUMO

The globally widespread adoption of Artificial Light at Night (ALAN) began in the mid-20th century. Yet, it is only in the last decade that a renewed research focus has emerged into its impacts on ecological and biological processes in the marine environment that are guided by natural intensities, moon phase, natural light and dark cycles and daily light spectra alterations. The field has diversified rapidly from one restricted to impacts on a handful of vertebrates, to one in which impacts have been quantified across a broad array of marine and coastal habitats and species. Here, we review the current understanding of ALAN impacts in diverse marine ecosystems. The review presents the current state of knowledge across key marine and coastal ecosystems (sandy and rocky shores, coral reefs and pelagic) and taxa (birds and sea turtles), introducing how ALAN can mask seabird and sea turtle navigation, cause changes in animals predation patterns and failure of coral spawning synchronization, as well as inhibition of zooplankton Diel Vertical Migration. Mitigation measures are recommended, however, while strategies for mitigation were easily identified, barriers to implementation are poorly understood. Finally, we point out knowledge gaps that if addressed would aid in the prediction and mitigation of ALAN impacts in the marine realm.


Assuntos
Antozoários , Ecossistema , Animais , Recifes de Corais , Luz , Poluição Luminosa
6.
Conserv Biol ; 36(1): e13724, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-33634525

RESUMO

Wildlife health assessments help identify populations at risk of starvation, disease, and decline from anthropogenic impacts on natural habitats. We conducted an overview of available health assessment studies in noncaptive vertebrates and devised a framework to strategically integrate health assessments in population monitoring. Using a systematic approach, we performed a thorough assessment of studies examining multiple health parameters of noncaptive vertebrate species from 1982 to 2020 (n = 261 studies). We quantified trends in study design and diagnostic methods across taxa with generalized linear models, bibliometric analyses, and visual representations of study location versus biodiversity hotspots. Only 35% of studies involved international or cross-border collaboration. Countries with both high and threatened biodiversity were greatly underrepresented. Species that were not listed as threatened on the International Union for Conservation of Nature Red List represented 49% of assessed species, a trend likely associated with the regional focus of most studies. We strongly suggest following wildlife health assessment protocols when planning a study and using statistically adequate sample sizes for studies establishing reference ranges. Across all taxa blood analysis (89%), body composition assessments (81%), physical examination (72%), and fecal analyses (24% of studies) were the most common methods. A conceptual framework to improve design and standardize wildlife health assessments includes guidelines on the experimental design, data acquisition and analysis, and species conservation planning and management implications. Integrating a physiological and ecological understanding of species resilience toward threatening processes will enable informed decision making regarding the conservation of threatened species.


Importancia de los exámenes diagnósticos para la conservación de fauna silvestre Resumen Los exámenes diagnósticos de fauna silvestre ayudan a identificar poblaciones en riesgo por desnutrición, enfermedades infecciosas y disminución poblacional, causadas por impactos antropogénicos. Revisamos los estudios disponibles que llevaron a cabo exámenes diagnósticos en fauna silvestre y diseñamos un marco de trabajo para integrar dichos exámenes en monitoreos poblacionales. Empleando un enfoque sistemático, evaluamos aquellos estudios que examinaban múltiples indicadores de salud en vertebrados no cautivos entre 1982 y 2020 (n = 261 estudios). Cuantificamos las tendencias estadísticas, clasificadas por taxones, del diseño del estudio y de los métodos diagnósticos usando modelos lineales generalizados, análisis bibliométricos y representaciones visuales del lugar de estudio versus los hotspots (puntos calientes) de biodiversidad. Sólo el 35% de los estudios incluían colaboraciones internacionales o transfronterizas, y los países ricos en biodiversidad y especies amenazadas estaban gravemente subrepresentados. Las especies no clasificadas como amenazadas en la Lista Roja de la Unión Internacional para la Conservación de la Naturaleza representaban el 49% de las especies examinadas; una tendencia posiblemente asociada al enfoque regional de la mayoría de los estudios. Recomendamos encarecidamente seguir protocolos diagnósticos y manuales de técnicas del estudio de la fauna silvestre, además de usar tamaños muestrales estadísticamente adecuados al establecer rangos de referencia. Los métodos diagnósticos más comunes para todos los taxones fueronanálisis sanguíneos (89%), evaluaciones de composición corporal (81%), exámenes físicos (72%) y análisis fecales (24% de los estudios). Presentamos un marco conceptual para mejorar y estandarizar los exámenes diagnósticos en estudios de fauna silvestre; dicho marco incluye guías para el diseño experimental, para la obtención y el análisis de datos, y para elaborar planes de acción para especies amenazadas. La combinación de conocimientos fisiológicos y ecológicos, relacionados con la resiliencia biológica de especies amenazadas, facilitará una toma de decisiones eficiente para el manejo y para la conservación de la biodiversidad.


Assuntos
Animais Selvagens , Conservação dos Recursos Naturais , Animais , Biodiversidade , Ecossistema , Espécies em Perigo de Extinção
7.
J Nat Prod ; 85(1): 292-300, 2022 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-34965131

RESUMO

Melastoma malabathricum is an Indo-Pacific herb that has been used traditionally to treat numerous ailments such as wounds, dysentery, diarrhea, toothache, and diabetes. The objective of this study was to evaluate the variability of the metabolic profiles of M. malabathricum across its geographic distribution. By employing thin layer chromatography (TLC), specimens collected from six terrestrial and archipelago regions of Indonesia were analyzed by densitometry for metabolomic fingerprinting analysis combined with chemometric tools: principal component analysis (PCA) and hierarchical cluster analysis (HCA). Two PCAs were identified as PC1 and PC2 with 41.90% and 20.36%, respectively. Our results indicate the importance of considering geographic distribution during field-collection efforts since they demonstrate regional metabolic variation in secondary metabolites of M. malabathricum, as illustrated by TLC and their biological activities.


Assuntos
Cromatografia em Camada Fina/métodos , Metabolômica , Myrtales/química , Análise por Conglomerados , Indonésia , Myrtales/classificação , Filogeografia , Análise de Componente Principal
8.
J Nat Prod ; 85(7): 1779-1788, 2022 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-35815804

RESUMO

Oxidative stress plays an important role in acetaminophen (APAP)-induced hepatotoxicity. Platanosides (PTSs) isolated from the American sycamore tree (Platanus occidentalis) represent a potential new four-molecule botanical drug class of antibiotics active against drug-resistant infectious disease. Preliminary studies have suggested that PTSs are safe and well tolerated and have antioxidant properties. The potential utility of PTSs in decreasing APAP hepatotoxicity in mice in addition to an assessment of their potential with APAP for the control of infectious diseases along with pain and pyrexia associated with a bacterial infection was investigated. On PTS treatment in mice, serum alanine aminotransferase (ALT) release, hepatic centrilobular necrosis, and 4-hydroxynonenal (4-HNE) were markedly decreased. In addition, inducible nitric oxide synthase (iNOS) expression and c-Jun-N-terminal kinase (JNK) activation decreased when mice overdosed with APAP were treated with PTSs. Computational studies suggested that PTSs may act as JNK-1/2 and Keap1-Nrf2 inhibitors and that the isomeric mixture could provide greater efficacy than the individual molecules. Overall, PTSs represent promising botanical drugs for hepatoprotection and drug-resistant bacterial infections and are effective in protecting against APAP-related hepatotoxicity, which decreases liver necrosis and inflammation, iNOS expression, and oxidative and nitrative stresses, possibly by preventing persistent JNK activation.


Assuntos
Acetaminofen , Doença Hepática Induzida por Substâncias e Drogas , Acetaminofen/farmacologia , Animais , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Combinação de Medicamentos , Glicosídeos , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fígado , Camundongos , Camundongos Endogâmicos C57BL , Fator 2 Relacionado a NF-E2/metabolismo , Necrose/induzido quimicamente , Necrose/tratamento farmacológico , Necrose/metabolismo , Estresse Oxidativo , Fenóis
9.
J Nat Prod ; 85(5): 1436-1441, 2022 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-35473311

RESUMO

Two new lactone lipids, scoriosin (1) and its methyl ester (2), with a rare furylidene ring joined to a tetrahydrofurandione ring, were isolated from Scorias spongiosa, commonly referred to as sooty mold. The planar structure of these compounds was assigned by 1D and 2D NMR. The conformational analysis of these molecules was undertaken to evaluate the relative and absolute configuration through GIAO NMR chemical shift analysis and ECD calculation. In addition to the potent antimicrobial activities, compound 2 strongly potentiated the activity of amphotericin B against Cryptococcus neoformans, suggesting the potential utility of this compound in combination therapies for treating cryptococcal infections.


Assuntos
Anti-Infecciosos , Cryptococcus neoformans , Antifúngicos/farmacologia , Ascomicetos , Lactonas/farmacologia , Lipídeos , Estrutura Molecular
10.
Mar Drugs ; 20(11)2022 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-36355002

RESUMO

This Special Issue is dedicated to the memory of Professor Paul J [...].

11.
Mar Drugs ; 20(10)2022 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-36286470

RESUMO

Manzamine-A is a marine-derived alkaloid which has anti-viral and anti-proliferative properties and is currently being investigated for its efficacy in the treatment of certain viruses (malaria, herpes, HIV-1) and cancers (breast, cervical, colorectal). Manzamine-A has been found to exert effects via modulation of SIX1 gene expression, a gene critical to craniofacial development via the WNT, NOTCH, and PI3K/AKT pathways. To date little work has focused on Manzamine-A and how its use may affect bone. We hypothesize that Manzamine-A, through SIX1, alters bone cell activity. Here, we assessed the effects of Manzamine-A on cells that are responsible for the generation of bone, pre-osteoblasts and osteoblasts. PCR, qrtPCR, MTS cell viability, Caspase 3/7, and functional assays were used to test the effects of Manzamine-A on these cells. Our data suggests Six1 is highly expressed in osteoblasts and their progenitors. Further, osteoblast progenitors and osteoblasts exhibit great sensitivity to Manzamine-A treatment exhibited by a significant decrease in cell viability, increase in cellular apoptosis, and decrease in alkaline phosphatase activity. In silico binding experiment showed that manzamine A potential as an inhibitor of cell proliferation and survival proteins, i.e., Iκb, JAK2, AKT, PKC, FAK, and Bcl-2. Overall, our data suggests Manzamine-A may have great effects on bone health overall and may disrupt skeletal development, homeostasis, and repair.


Assuntos
Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatase Alcalina/metabolismo , Caspase 3/metabolismo , Osteoblastos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Diferenciação Celular , Osteogênese
12.
J Nat Prod ; 84(3): 738-749, 2021 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-33606538

RESUMO

Nine new glucosyloxybenzyl 2-hydroxy-2-isobutylsuccinates, pleionosides M-U (1-9), and 12 known compounds (10-21) were isolated from the pseudobulbs of Pleione yunnanensis. Their structures and absolute configurations were established through a combination of HRESIMS and NMR data and supported by physical and chemical methods. Compounds 5, 6, 10, and 15 showed significant in vitro hepatoprotective activity against d-galactosamine (d-GalN)-induced toxicity in HL-7702 cells with increasing cell viability by 27%, 22%, 19%, and 31% compared to the model group (cf. bicyclol, 14%) at 10 µM, respectively. Compounds 4, 9, and 11 exhibited moderate hepatoprotective activity against N-acetyl-p-aminophenol (APAP)-induced toxicity in HepG2 cells with increasing cell viability by 9%, 16%, and 12% compared to the model group (cf. bicyclol, 9%) at 10 µM, respectively.


Assuntos
Orchidaceae/química , Substâncias Protetoras/farmacologia , Succinatos/farmacologia , Acetaminofen , Sobrevivência Celular/efeitos dos fármacos , China , Células Hep G2 , Humanos , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Substâncias Protetoras/isolamento & purificação , Succinatos/isolamento & purificação
13.
J Nat Prod ; 84(11): 3001-3007, 2021 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-34677966

RESUMO

The pressing need for SARS-CoV-2 controls has led to a reassessment of strategies to identify and develop natural product inhibitors of zoonotic, highly virulent, and rapidly emerging viruses. This review article addresses how contemporary approaches involving computational chemistry, natural product (NP) and protein databases, and mass spectrometry (MS) derived target-ligand interaction analysis can be utilized to expedite the interrogation of NP structures while minimizing the time and expense of extraction, purification, and screening in BioSafety Laboratories (BSL)3 laboratories. The unparalleled structural diversity and complexity of NPs is an extraordinary resource for the discovery and development of broad-spectrum inhibitors of viral genera, including Betacoronavirus, which contains MERS, SARS, SARS-CoV-2, and the common cold. There are two key technological advances that have created unique opportunities for the identification of NP prototypes with greater efficiency: (1) the application of structural databases for NPs and target proteins and (2) the application of modern MS techniques to assess protein-ligand interactions directly from NP extracts. These approaches, developed over years, now allow for the identification and isolation of unique antiviral ligands without the immediate need for BSL3 facilities. Overall, the goal is to improve the success rate of NP-based screening by focusing resources on source materials with a higher likelihood of success, while simultaneously providing opportunities for the discovery of novel ligands to selectively target proteins involved in viral infection.


Assuntos
Antivirais/farmacologia , Betacoronavirus/efeitos dos fármacos , Produtos Biológicos/farmacologia , Descoberta de Drogas , Biologia Computacional , Bases de Dados de Compostos Químicos , Bases de Dados de Proteínas , Ligantes , Espectrometria de Massas , Mapeamento de Interação de Proteínas , SARS-CoV-2/efeitos dos fármacos
14.
Mar Drugs ; 19(9)2021 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-34564169

RESUMO

Manzamines are complex polycyclic marine-derived ß-carboline alkaloids with reported anticancer, immunostimulatory, anti-inflammatory, antibacterial, antiviral, antimalarial, neuritogenic, hyperlipidemia, and atherosclerosis suppression bioactivities, putatively associated with inhibition of glycogen synthase kinase-3, cyclin-dependent kinase 5, SIX1, and vacuolar ATPases. We hypothesized that additional, yet undiscovered molecular targets might be associated with Manzamine A's (MZA) reported pharmacological properties. We report here, for the first time, that MZA selectively inhibited a 90 kDa ribosomal protein kinase S6 (RSK1) when screened against a panel of 30 protein kinases, while in vitro RSK kinase assays demonstrated a 10-fold selectivity in the potency of MZA against RSK1 versus RSK2. The effect of MZA on inhibiting cellular RSK1 and RSK2 protein expression was validated in SiHa and CaSki human cervical carcinoma cell lines. MZA's differential binding and selectivity toward the two isoforms was also supported by computational docking experiments. Specifically, the RSK1-MZA (N- and C-termini) complexes appear to have stronger interactions and preferable energetics contrary to the RSK2-MZA ones. In addition, our computational strategy suggests that MZA binds to the N-terminal kinase domain of RSK1 rather than the C-terminal domain. RSK is a vertebrate family of cytosolic serine-threonine kinases that act downstream of the ras-ERK1/2 (extracellular-signal-regulated kinase 1/2) pathway, which phosphorylates substrates shown to regulate several cellular processes, including growth, survival, and proliferation. Consequently, our findings have led us to hypothesize that MZA and the currently known manzamine-type alkaloids isolated from several sponge genera may have novel pharmacological properties with unique molecular targets, and MZA provides a new tool for chemical-biology studies involving RSK1.


Assuntos
Antineoplásicos/uso terapêutico , Carbazóis/uso terapêutico , Poríferos , Neoplasias do Colo do Útero/tratamento farmacológico , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Organismos Aquáticos , Carbazóis/química , Carbazóis/farmacologia , Feminino , Humanos , Sistema de Sinalização das MAP Quinases , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Simulação de Acoplamento Molecular
15.
Angew Chem Int Ed Engl ; 60(41): 22270-22275, 2021 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-34374477

RESUMO

Forrestiacids A (1) and B (2) are a novel class of [4+2] type pentaterpenoids derived from a rearranged lanostane moiety (dienophile) and an abietane unit (diene). These unprecedented molecules were isolated using guidance by molecular ion networking (MoIN) from Pseudotsuga forrestii, an endangered member of the Asian Douglas Fir Family. The intermolecular hetero-Diels-Alder adducts feature an unusual bicyclo[2.2.2]octene ring system. Their structures were elucidated by spectroscopic analysis, GIAO NMR calculations and DP4+ probability analyses, electronic circular dichroism calculations, and X-ray diffraction analysis. This unique addition to the pentaterpene family represents the largest and the most complex molecule successfully assigned using computational approaches to predict accurately chemical shift values. Compounds 1 and 2 exhibited potent inhibitory activities (IC50 s <5 µM) of ATP-citrate lyase (ACL), a new drug target for the treatment of glycolipid metabolic disorders including hyperlipidemia. Validating this activity 1 effectively attenuated the de novo lipogenesis in HepG2 cells. These findings provide a new chemical class for developing potential therapeutic agents for ACL-related diseases with strong links to traditional medicines.


Assuntos
ATP Citrato (pro-S)-Liase/antagonistas & inibidores , Produtos Biológicos/farmacologia , Inibidores Enzimáticos/farmacologia , Terpenos/farmacologia , ATP Citrato (pro-S)-Liase/metabolismo , Produtos Biológicos/química , Inibidores Enzimáticos/química , Humanos , Lipogênese/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Conformação Molecular , Terpenos/química
16.
J Anim Ecol ; 89(4): 1008-1016, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31785174

RESUMO

Patterns of animal movement associated with foraging lie at the heart of many ecological studies and often animals face decisions of staying in an environment they know versus relocating to new sites. The lack of knowledge of new foraging sites means there is risk associated with a decision to relocate (e.g. poor foraging) as well as a potential benefit (e.g. improved foraging). Using a unique long-term satellite tracking dataset for several sea turtle species, combined with capture-mark-recapture data extending over 50 years, we show how, across species, individuals generally maintain tight fidelity to specific foraging sites after extended (up to almost 10,000 km) migration to and from distant breeding sites as well as across many decades. Migrating individuals often travelled through suitable foraging areas en route to their 'home' site and so extended their journeys to maintain foraging site fidelity. We explore the likely mechanistic underpinnings of this trait, which is also seen in some migrating birds, and suggest that individuals will forgo areas of suitable forage encountered en route during migration when they have poor knowledge of the long-term suitability of those sites, making relocation to those sites risky.


Assuntos
Tartarugas , Animais , Aves , Cruzamento
17.
J Nat Prod ; 83(2): 286-295, 2020 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-32022559

RESUMO

Natural products remain an important source of drug leads covering unique chemical space and providing significant therapeutic value for the control of cancer and infectious diseases resistant to current drugs. Here, we determined the antiproliferative activity of a natural product manzamine A (1) from an Indo-Pacific sponge following various in vitro cellular assays targeting cervical cancer (C33A, HeLa, SiHa, and CaSki). Our data demonstrated the antiproliferative effects of 1 at relatively low and non-cytotoxic concentrations (up to 4 µM). Mechanistic investigations confirmed that 1 blocked cell cycle progression in SiHa and CaSki cells at G1/S phase and regulated cell cycle-related genes, including restoration of p21 and p53 expression. In apoptotic assays, HeLa cells showed the highest sensitivity to 1 as compared to other cell types (C33A, SiHa, and CaSki). Interestingly, 1 decreased the levels of the oncoprotein SIX1, which is associated with oncogenesis in cervical cancer. To further investigate the structure-activity relationship among manzamine A (1) class with potential antiproliferative activity, molecular networking facilitated the efficient identification, dereplication, and assignment of structures from the manzamine class and revealed the significant potential in the design of optimized molecules for the treatment of cervical cancer. These data suggest that this sponge-derived natural product class warrants further attention regarding the design and development of novel manzamine analogues, which may be efficacious for preventive and therapeutic treatment of cancer. Additionally, this study reveals the significance of protecting fragile marine ecosystems from climate change-induced loss of species diversity.


Assuntos
Apoptose/efeitos dos fármacos , Produtos Biológicos/farmacologia , Carbazóis/farmacologia , Proteínas de Homeodomínio/metabolismo , Neoplasias do Colo do Útero/tratamento farmacológico , Produtos Biológicos/química , Carbazóis/química , Linhagem Celular Tumoral , Ecossistema , Feminino , Células HeLa , Proteínas de Homeodomínio/química , Humanos , Relação Estrutura-Atividade , Neoplasias do Colo do Útero/química
18.
J Nat Prod ; 83(4): 1092-1098, 2020 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-32227883

RESUMO

The natural product veranamine was isolated from the marine sponge Verongula rigida. It contains a unique heterocyclic scaffold and demonstrates in vivo antidepressant activity and selective affinity for 5HT2B and sigma-1 receptors. The first total synthesis of veranamine is reported. Our scalable synthesis offers veranamine in six steps and 25% yield via an unprecedented vinylogous Pictet-Gams pyridine formation strategy. Veranamine is a promising new lead compound for antidepressant drug development.


Assuntos
Antidepressivos/farmacologia , Poríferos/química , Animais , Antidepressivos/química , Antidepressivos/isolamento & purificação , Estrutura Molecular
19.
J Environ Manage ; 262: 110311, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32250794

RESUMO

Human societies are closely linked to their ecological environments. Natural ecosystems and wildlife populations are often in better condition in countries with healthy, educated and economically prosperous populations compared to countries with lower health and literacy conditions, and depressed economies. In the latter countries, these socio-economic factors can compromise government's capacity to manage their natural resources. Thus, the conservation capacity of a government is likely to play key role in the protection of threatened species, such as marine turtles. This paper aims: (1) to evaluate the conservation capacity and enforcement within the 58 Regional Management Units (RMUs) of the seven species of marine turtles throughout the world, and (2) to develop a proxy that predicts the conservation status of RMUs. We developed a Conservation and Enforcement Capacity index (CECi) by integrating the following indices: (a) the economic level and, (b) the Human Development Index (HDI) of each country, plus (c) the risks and threats in the RMUs. We used the conservation status of 15 RMUs recently assessed by the International Union for Conservation of Nature - IUCN to predict the conservation status of the 43 RMUs without updated IUCN categorisation. CECi values ranged from 0 to 1, where lower values represent a better capacity for implementation of conservation initiatives. We found that using our multi-index model, we predicted the status of 33 of 58 RMUs, 57% of which may be of threatened conservation status due to their high CECi values. This study highlighted how socio-economic aspects may impact conservation of endangered species.


Assuntos
Tartarugas , Animais , Animais Selvagens , Conservação dos Recursos Naturais , Ecossistema , Espécies em Perigo de Extinção , Humanos
20.
J Am Chem Soc ; 141(10): 4338-4344, 2019 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-30758203

RESUMO

We report here the orchestration of molecular ion networking and a set of computationally assisted structural elucidation approaches in the discovery of a new class of pyrroloiminoquinone alkaloids that possess selective bioactivity against pancreatic cancer cell lines. Aleutianamine represents the first in a new class of pyrroloiminoquinone alkaloids possessing a highly strained multibridged ring system, discovered from Latrunculia ( Latrunculia) austini Samaai, Kelly & Gibbons, 2006 (class Demospongiae, order Poecilosclerida, family Latrunculiidae) recovered during a NOAA deep-water exploration of the Aleutian Islands. The molecule was identified with the guidance of mass spectrometry, nuclear magnetic resonance, and molecular ion networking (MoIN) analysis. The structure of aleutianamine was determined using extensive spectroscopic analysis in conjunction with computationally assisted quantifiable structure elucidation tools. Aleutianamine exhibited potent and selective cytotoxicity toward solid tumor cell lines including pancreatic cancer (PANC-1) with an IC50 of 25 nM and colon cancer (HCT-116) with an IC50 of 1 µM, and represents a potent and selective candidate for advanced preclinical studies.


Assuntos
Antineoplásicos/farmacologia , Alcaloides Indólicos/farmacologia , Alaska , Animais , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Linhagem Celular Tumoral , Descoberta de Drogas , Humanos , Alcaloides Indólicos/química , Alcaloides Indólicos/isolamento & purificação , Camundongos , Modelos Químicos , Estrutura Molecular , Poríferos/química , Estereoisomerismo
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